Cambering vehicle

ABSTRACT

A three-wheeled cambering vehicle having a platform for supporting the vehicle operator and having a pair of laterally spaced rear wheels mounted thereon. The vehicle has a centralized tubular frame with a front leg member that supports a steerable front fork and wheel assembly and a rearward seat for the vehicle operator. A lower leg of the frame is supported for turning movement with respect to a longitudinal roll axis by the platform which permits the frame and front fork and wheel assembly to be cambered by the vehicle operator as the platform remains in a predetermined plane with respect to the support surface.

This invention relates to a new and improved three-track camberingvehicle for supporting an operator in a seated position while allowingthe operator to impart balancing moments into the vehicle through hisfeet selectively positioned on a platform carried by the vehicle frameand maintained in a substantially fixed plane by rear contacts as afront steering assembly, the frame and attached seat are cambered withrespect to the platform.

Prior to the present invention, narrow three-track cambering vehicleshave had various suspension arrangements so that the vehicle frame andwheels or other surface contact means could be cambered for improvedmobility and stability. For example, my prior U.S. Pat. No. 4,087,106for Cambering Vehicle issued May 2, 1978 discloses a vehicle in whichtrailing arms are pivotally mounted to a front frame member so the frontand rear contacts can be cambered with the frame to permit a vehicleoperator, preferably while standing, to lean with the vehicle in anatural manner to execute cornering and other vehicle maneuvers with ahigh degree of stability. While my prior cambering vehicle provided ahighly stabilized and maneuverable vehicle and functioned as intended,it was determined that a somewhat similar vehicle having a platformmaintained in a fixed plane with respect to the ground was desirable sothat a seated operator could put balancing moments into the vehicle asit is being maneuvered using the platform as a moving ground. To thisend the present invention is drawn to a lightweight three-place contactcambering vehicle in which a steerable front contact and a centralizedvehicle frame with a seat for operator support can be cambered while aplatform remains in a substantially horizontal plane; i.e., a plane,fixed with respect to the supporting surface. Laterally spaced rearcontacts are carried by the platform and cannot be cambered with theframe, seat, and front contact. The platform, in effect, provides aground moving with the vehicle on which the seated operator places hisfeet spread apart on opposite sides of the vehicle roll axis. In thisposition, the operator preferably performs coordinated cambered vehiclemaneuvers such as high-speed cornering without utilization of footbalance input. If, however, there is a loss of balance, the operator canselectively impart left and right balancing loads through feet groundedon the platform to regain balance and to thereby improve control. Whenthe vehicle is at a standstill, the operator can impart foot balancingmoments to the platform to maintain the vehicle upright and ready formovement without his feet contacting the roadway on opposite sides ofthe vehicle, as would be the case with a conventional motorcycle ormo-ped. While the operator preferably drives the vehicle while seated,he may optionally stand on the support platform during vehicle operationincluding all maneuvers.

It is a feature, object and advantage of this invention to provide a newand improved cambering vehicle with a centralized cambering framesupporting a steerable front ground contact and an operator supportingseat; a platform for receiving the feet of the operator and rockablysupporting the frame is stabilized with respect to the supportingsurface by laterally spaced rear contacts carried thereby to allow theoperator to impart balancing moment to the vehicle through his feet asthe vehicle frame, seat and front contact are cambered.

Another feature, object and advantage of this invention is to provide anew and improved narrow-track vehicle with high lateral accelerationpotential produced by cambering the main frame and a steerable frontwheel; laterally spaced rear wheels are mounted on a generallyhorizontal platform which remains in a plane substantially fixed withrespect to the ground during cornering and other vehicle maneuvers.

Another feature, object and advantage of this invention is to provide anew and improved three-wheel cambering vehicle having a frame with anoperator's seat fixed thereto which incorporates a new and improvedplatform that carries the rear wheels and rockably supports the framefor cambering movement and that remains substantially parallel withrespect to the support surface during vehicle maneuvers includingcambering of the steering wheel, seat and frame.

Another feature, object and advantage of this invention is to provide anew and improved cambering vehicle having a steerable front supportmounted on a cambering frame extending along longitudinal axis of thevehicle and having a pair of laterally spaced rear supports and platformmounted on the cambering frame in a manner such that the platformremains substantially parallel to the support surface as the frame andfront contact are cambered.

These and other features, objects and advantages of this invention willbe more apparent from the following detailed description and drawings inwhich:

FIG. 1 is a perspective view of a vehicle illustrating a preferredembodiment of this invention;

FIG. 2 is a top plan view of a portion of the vehicle of FIG. 1;

FIG. 3 is an end view of a portion of the vehicle of FIG. 1;

FIG. 4 is a side view, partially in section, of the vehicle of FIG. 1;

FIG. 5 is an end view, partially in section, of a portion of the vehicleof FIG. 1;

FIG. 6 is a bottom plan view, with parts broken away, of the vehicle ofFIG. 1;

FIG. 7 is an enlarged view of a portion of the vehicle of FIG. 4;

FIG. 8 is a cross-sectional view taken along lines 8--8 of FIG. 7 asviewed in the direction of the sight line arrows.

Turning now in greater detail to the drawing, there is shown in FIG. 1 athree-wheeled cambering vehicle 12 for providing individual mobility foran operator. This three-track vehicle has a centralized tubular mainframe 14, generally L-shaped in side view configuration with an upwardlyinclined front leg portion 16. The forward leg portion supports at itsupper end a tubular collar 18, inclined at a predetermined rake angle,in which a steering post 20 is rotatably journaled. The upper end of thesteering post 20 is connected to a handlebar assembly 22 by a goosenecktype connection 24.

The steering post 20 may be turned in clockwise or counterclockwisedirection within the collar 18 by the manual activation of the handlebarassembly 22 by a vehicle operator sitting or standing on the vehicle.The steering post 20 is connected by upper bracket 26 and lower bracket28 to an inclined dual bar steering fork assembly 30.

A front axle 32 supported on the lower end of the fork assembly 30rotatably mounts a front road wheel 34 steerable through the turning ofthe fork assembly through the steering post and handlebar assembly. Asprocket 36, drivingly connected to the front wheel 34, is driven by aninternal combustion engine 38 through an endless chain 40. The enginemounted to the front fork assembly may be started by pulling a startercable 42 by means of a handle 44 mounted on the gooseneck connection 24by a bracket 46. Engine speed is controlled through a rotatablehandlebar grip 48 operatively connected through a suitable cable to thethrottle valve of the engine. Pull cable 49 mounted on the handlebarassembly adjacent to the grip 48 controls the engine choke.

The tubular main frame 14 extends in a longitudinal plane that bisectsthe vehicle. In addition to leg portion 16, the main frame has a lowerleg portion 50 that extends rearwardly and slightly upwardly from thebottom of the front leg portion 16. The central longitudinal axis A ofthe lower leg portion 50 describes the roll axis of the vehicle and isinclined at a predetermined angle to intersect the support surface at,forward or aft of footprint P of the front wheel 34 to provide aselected steering characteristic.

An operator supporting platform 52 formed by a contoured shell isrockably mounted on the lower leg portion 50 of the main frame forcambering operations. To this end the platform 52 has a centralized andlongitudinally extending tunnel 54 in which support tube 56 is mounted.

The lower leg 50 of the frame extends through and is rotatably mountedwithin the support tube 56 by respective front and rear bearings 58 and60 which allow the main frame to be cambered clockwise orcounterclockwise about axis A and with respect to the platform asillustrated in FIGS. 3 and 5.

The bearings 58 and 60 are substantially the same in construction sothat only bearing 58 is described in detail. As shown in FIGS. 7 and 8,the front bearing 58 comprises a cylindrical bushing 61 of nylon orother suitable material mounted in the forward end of the support tube56. Annular retainer 64 mounted on the lower leg portion 50 immediatelyin front of the bushing 61 retains the bushing in place within theconfines of the support tube.

The platform 52 is a lightweight component and preferably is formed froma plastic shell filled with a reinforcing closed celled plasticmaterial. In a top plan configuration, the platform is somewhattriangular as shown in FIGS. 2 and 6. The forward portion of thisplatform is arched upwardly as shown in FIGS. 1 and 4 while the rearcorners are formed with arched fenders 68 and 70 to accommodate thelaterally spaced rear wheels 72 and 74. The rear wheels are supported ona rear axle 76 which is mounted within a cylindrical cross tube 78extending laterally across the rear end of the platform 52. The crosstube 78 is secured to aft end of the centralized support tube 56 by adepending arm 80 as best shown in FIGS. 4 and 5. The outboard ends ofthe cross tube 78 are secured by angular brackets 84 and 86 to theunderside of the platform 52 as shown in FIG. 6. Mounted to the brackets84 and 86 are left and right stationary housings 88 and 90 that containscam-operated shoe brakes. These shoe brakes are engaged with associatedbrake drums not shown through a laterally extending brake shaft 92turned by crank arms 94 on actuation of a braking cable 96 which extendsalong the bottom of the support platform and up to a manual brake lever98 mounted on the handlebar assembly adjacent to left hand handlebargrip 100.

Extending upwardly from the rear end of the lower leg portion 50 of theframe 14 is a telescoping spring strut 102 assembly that incorporatesthe depending support post 104 of the saddle-type operator's seat 106.Seat height adjustment is made in conventional manner by looseninggripping collar 108, telescoping the seat post to set the seat at thedesired height and retightening collar 108 to grip the seat post. Thestrut 102 is protected by a convoluted plastic cover 109.

The operator may be seated on the seat with his feet placed in anyselected position on opposite sides 110, 112 of the platform includingthe outer preimeter thereof. Balancing moments can be imparted throughthe feet on the platform to keep the vehicle upright when stationary.The vehicle engine can then be started in conventional manner and thevehicle driven forwardly. With the platform moving in a relatively fixedplane, the operator can lean naturally into turns while seated duringvehicle operation since the seat and its supporting spring strut arefixed to the cambering main frame and move through the same camberangle. With the platform riding in a fixed plane about the roadway andwith the operator leaning into a turn along with the frame, seat andfront steering assembly, the operator can, if necessary, impress loadsonto the platform through his feet at all speeds from zero to maximumfor lateral balancing. For example, when executing a sharp turn, theoperator can steer the vehicle into the turn at a large camber angle.Normally the operator stays coordinated as on a motorcycle so that thevehicle is in equilibrium. If, however, an unbalanced condition occurs,the operator can use foot balance moments as required to regain vehicleequilibrium without his feet contacting the ground. With the movingplatform serving as a ground, there would be no need for the operatorusing his feet for contact with the road surface to serve as a skid inorder to impart balancing moments, as might be the case when cornering aconventional two-wheeled motorcycle. For evasive maneuvers, the operatorcan use his feet to camber the vehicle of this invention quicker than aconventional motorcycle can be cambered since no momentary steeringinput opposite to the direction of camber is necessary with thisinvention.

The vehicle can also be readily ridden with the operator standing in anatural manner on the platform. During such cornering operation, theoperator can camber the vehicle by leaning the frame and the frontsteering fork for stabilized cornering at a wide range of vehicle speed.During the maneuvers, the platform will remain parallel or at a fixedangle with respect to the supporting surface.

With this narrow-track cambering vehicle, narrow and tortuous paths canbe readily negotiated with a proper match of vehicle speed, camber angleand path curvature to maintain lateral stability. For parking, hook 114pivoted to main frame leg 16 is moved from an upper over-center positioninto locking engagement with the apex of the platform to secure theplatform to the main frame so that the vehicle will stand freely.

While a preferred embodiment of the invention has been shown anddescribed to illustrate the invention, other modifications will becomeapparent to those skilled in the art. Accordingly, the scope of thisinvention is set forth in the following claims.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. A cambering vehicle fortransporting a vehicle operator along a support surface, said vehiclecomprising a centralized main frame having an upwardly extending forwardframe member and a lower tubular frame member extending along thelongitudinal axis of the vehicle rearwardly from the lower end of saidforward frame member to the rear of said vehicle, steerable front wheelmeans supported by said forward frame member for contacting said supportsurface, manual steering means operatively connected to said steerablefront wheel means, a seat for a vehicle operator attached to said lowerframe member, a one-piece support platform extending to the rear of saidvehicle from said forward frame member and laterally across said lowerframe member for receiving the feet of the vehicle operator, bearingmeans operatively connecting said lower frame member to said platformfor supporting said frame on said platform for free cambering movementabout a longitudinal roll axis coplanar with the longitudinal axis ofsaid platform, transverse axle means rotatably supporting the centralframe secured to said platform, rear wheel means underlying said seatmeans and supported on opposite outboard ends of said axle means forcontacting said support surface to support said platform in fixedangular relationship with respect to said support surface while allowingthe operator when seated to impart balancing moments through his feetwhile cambering said central frame and said front wheel means.
 2. Acambering vehicle for transporting a vehicle operator along a supportsurface, said vehicle comprising a central tubular frame having anupwardly extending forward frame member and a lower frame memberextending along the longitudinal axis of the vehicle rearwardly from thelower end of said forward frame member to the end of said vehicle,steerable front wheel means supported by said forward frame member forcontacting said support surface, manual steering means operativelyconnected to said steerable front wheel means, a shell-like supportplatform having a centralized longitudinal axis extending to the rear ofsaid vehicle from said forward frame member and laterally across saidlower frame member for receiving the feet of the vehicle operator,bearing means pivotally connecting said lower frame member to saidplatform for supporting said frame on said platform for substantiallyunrestrained clockwise and counterclockwise pivotal movement about alongitudinal roll axis coplanar with the longitudinal axis of saidvehicle, transverse rear axle means secured to said platform, rear wheelmeans supported on opposite outboard ends of said axle means forcontacting said support surface to support said platform in fixedangular relationship with respect to said support surface while allowingsaid operator to stand in a natural upright manner on said platform andstraddle said longitudinal roll axis to impart balancing moments whilesimultaneously cambering said frame and said front wheel means.
 3. Acambering vehicle for transporting a vehicle operator along a supportsurface, said vehicle comprising a centralized main cambering framehaving an upwardly extending forward frame member and a tubular lowerframe member extending along the longitudinal axis of said vehicle andrearwardly from the lower end of said forward frame member, a seat forthe vehicle operator, an upright for said seat extending upwardly fromthe trailing end portion of said lower frame member for camberingmovement therewith, steerable front wheel means supported by saidforward frame member for contacting said support surface, manualsteering means operatively connected to said steerable front wheelmeans, an operator support platform extending rearwardly from saidforward frame member to said upright and extending laterally across saidlower frame member for receiving the feet of the vehicle operator,bearing means operatively connecting said lower frame member to saidplatform for supporting said cambering frame on said platform forunrestrained cambering moments about a longitudinal roll axis coplanarwith the longitudinal axis of said vehicle, transverse rear axle meanssecured to said platform, rear wheel means supported on oppositeoutboard ends of said axle means for contacting said support surface tosupport said platform in a predetermined angular relationship withrespect to said support surface while allowing said operator to sit onsaid seat and straddle the longitudinal roll axis to impart balancingmoments while cambering said seat with said main frame and said frontwheel means. .Iadd.
 4. In a cambering vehicle having an engine forvehicle propulsion, a cambering steering fork assembly at the front ofthe vehicle mounting a road wheel at the lower end thereof and manualsteering means at the upper end thereof, a pair of laterally spaced rearroad wheels supporting a non-cambering support platform for the feet ofthe vehicle operator, a cambering main frame having a forward portionoperatively mounting the steering fork assembly and a cambering seatsupport at the rear of the vehicle for the vehicle operator connected tothe main frame for cambering movement therewith about a camber axis toallow the operator to freely lean into turns while standing or seatedand while cambering the vehicle with his feet on the support platformcharacterized in that the engine is mounted on the steering forkassembly and is drivingly connected to the front wheel of the steeringfork assembly and that the support platform extends between the forwardportion of the main frame and the seat support and is substantiallyunobstructed to facilitate operator entry and egress and operatorstabilization of the vehicle during powered cambering maneuvers throughfoot impressed loads to the platform in the event an unbalancedcondition occurs..Iaddend. .Iadd.5. A cambering vehicle according toclaim 4 characterized in that the seat support overlies a rearward endportion of the support platform and the rear wheels carried thereby..Iaddend. .Iadd.6. A cambering vehicle according to claim 4characterized in that the main frame includes a tubular andlongitudinally extending member that is coextensive with and is pivotedto the support platform. .Iaddend. .Iadd.7. A cambering vehicleaccording to claim 6 characterized in that the support platform is aunitized shell which supports and covers the rear wheels adjacent to therearward end thereof and which houses bearing means for said tubularmember of said main frame..Iaddend. .Iadd.8. A cambering vehicleaccording to claim 7 characterized in that the main frame extends alongthe longitudinal axis of the vehicle from rigid connection with the seatsupport at the rear of the vehicle into pivotal connection with thesteering fork assembly and that the tubular member of the main frame isa lower leg portion that encompasses the cambering axis of the steeringfork assembly and main frame. .Iaddend.